In a standard installation AEM creates a new version of a page or node when you activate a page after updating the content.

Note:

If no content changes are made then you will see the message stating that the page has been activated, but no new version will be created

You can create additional versions on request using the Versioning tab of the sidekick. These versions are stored in the repository and can be restored if required.

These versions are never purged, so the repository size will grow over time and therefore need to be managed.

AEM is shipped with various mechanisms to help you manage your repository:

the Version Manager
This can be configured to purge old versions when new versions are created.

the Purge Versionstool
This is used as part of monitoring and maintaining your repository.
It allows you to intervene to remove old versions of a node, or a hierarchy of nodes, according to these parameters:

The maximum number of versions to be kept in the repository.
When this number is exceeded, the oldest version is removed.

The maximum age of any version kept in the repository.
When the age of a version exceeds this value, it is purged from the repository.

Version Manager

In addition to explicit purging by means of the purge tool, the Version Manager can be configured to purge old versions when new versions are created.

To configure the Version Manager, create a configuration for:

PID com.day.cq.wcm.core.impl.VersionManagerImpl

The following options are available:

versionmanager.createVersionOnActivation (Boolean, default: true)
whether to create a version when pages are activated.
A version is created unless the replication agent is configured to suppress creation of versions, which is honoured by the Version Manager
A version is only created if the activation happens on a paths that is contained in versionmanager.ivPaths (see below).

versionmanager.ivPaths (String[], default: {"/"})
paths on which versions are implicitly created on activation if versionmanager.createVersionOnActivation is true.

versionmanager.purgingEnabled (Boolean, default: false)
whether to enable purging when new versions are created

versionmanager.purgePaths (String[], default: {"/content"})
on which paths to purge versions when new versions are created

versionmanager.maxAgeDays (int, default: 30)
on purge, any version older than this value will be removed. If this value is less than 1, purging is not performed based on the age of the version

versionmanager.maxNumberVersions (int, default 5)
on purge, any version older than the n-th newest version will be removed. If this value is less than 1, purging is not performed based on the number of versions

Note:

maxAgeDays and maxNumberVersions work together as follows:

For example :

Setting:

maxNumberVersions = 7

maxAgeDays = 30

With:

10 versions made within the past 60 days

3 of those versions created within the past 30 days

Will mean that:

the last 3 versions will be retained

Purge Versions Tool

The Purge Versions tool is intended for purging the versions of a node or a hierarchy of nodes in your repository. Its primary purpose is to help you reduce the size of your repository by removing old versions of your nodes.

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